Efficient Memoization Algorithms for Query Optimization: Top-Down Join Enumeration through Memoization on the Basis of Hypergraphs

For a DBMS that provides support for a declarative query language like SQL, the query optimizer is a crucial piece of software. The declarative nature of a query allows it to be translated into many equivalent evaluation plans. The process of choosing a suitable plan from all alternatives is known as query optimization. The basis of this choice are a cost model and statistics over the data. Essent...